Sheet manufacturing apparatus

Abstract

A sheet manufacturing apparatus includes a first frame on which an accumulation belt and a first suction unit are installed and a second frame on which a transport belt and a second suction unit are installed. An eccentric cam is disposed between the first frame and the second frame. A position of the second frame with respect to the first frame is changed by rotation of the eccentric cam.

What is claimed is: 
     
         1 . A sheet manufacturing apparatus for manufacturing a sheet from a material containing a fiber, the sheet manufacturing apparatus comprising:
 an accumulation unit configured to accumulate the material by using airflow to form a web;   a transport unit configured to transport the web; and   a pressing unit configured to press the web to form the sheet, wherein   the accumulation unit includes:
 a drum member configured to stir the material; 
 an accumulation belt on which the material discharged from the drum member is accumulated; 
 a first suction unit disposed on an opposite side of the accumulation belt from the drum member and configured to perform suction to accumulate the material on the accumulation belt; and 
 a first frame on which the accumulation belt and the first suction unit are installed, 
   the transport unit includes:
 a transport belt configured to come into contact with a first surface of the web to hold the web; 
 a second suction unit disposed above the transport belt and configured to perform suction to hold the web by suction; and 
 a second frame on which the transport belt and the second suction unit are installed, 
   an eccentric cam is disposed between the first frame and the second frame, and   a position of the second frame with respect to the first frame is changed by rotation of the eccentric cam.   
     
     
         2 . The sheet manufacturing apparatus according to  claim 1 , further comprising:
 a drive motor configured to rotate the eccentric cam.   
     
     
         3 . The sheet manufacturing apparatus according to  claim 1 , wherein
 the second frame is configured to be moved up from a first position with respect to the first frame to a second position that is higher than the first position by rotation of the eccentric cam.   
     
     
         4 . The sheet manufacturing apparatus according to  claim 3 , wherein
 the second frame is configured to be moved down from the second position to the first position by rotation of the eccentric cam.   
     
     
         5 . The sheet manufacturing apparatus according to  claim 3 , wherein
 L 2 >L 1 , where L 1  is a clearance between the accumulation belt and the transport belt when the second frame is positioned at the first position, and L 2  is a clearance between the accumulation belt and the transport belt when the second frame is positioned at the second position.   
     
     
         6 . The sheet manufacturing apparatus according to  claim 1 , wherein
 the eccentric cam has a protrusion, and   a detection unit configured to detect whether the eccentric cam is positioned at a home position by determining presence or absence of the protrusion is disposed close to the protrusion.   
     
     
         7 . The sheet manufacturing apparatus according to  claim 1 , further comprising:
 a humidifying unit facing the transport belt and configured to apply moisture to a second surface of the web.   
     
     
         8 . The sheet manufacturing apparatus according to  claim 3 , wherein
 when a front end of the web is held by suction on the transport belt, the second frame is positioned at the first position.   
     
     
         9 . The sheet manufacturing apparatus according to  claim 7 , wherein
 after the web is held by suction on the transport belt, the eccentric cam is rotated to move up the second frame from a first position to a second position before a front end of the web passes over the humidifying unit.   
     
     
         10 . The sheet manufacturing apparatus according to  claim 7 , wherein
 after a front end of the web passes over the humidifying unit, the eccentric cam is rotated to move down the second frame from a second position to a first position.   
     
     
         11 . The sheet manufacturing apparatus according to  claim 3 , wherein
 when the web is torn off, the eccentric cam is rotated to move up the second frame from the first position to the second position.